This invention relates to a paint substitute film used as substitutes for painting of exterior components of an automobile or the like.
In order to improve an ornamental design of exterior components or trims, such as fenders, bumpers, hoods, wheel caps, and other plastic components, of a vehicle, spray paint is employed in most instances. However, a painting process including an operation of spraying paint requires a large facility and wide space for repeatedly performed painting and drying steps and thus would disadvantageously reduce productivity and manageability. In this respect, an alternative approach has been sought, and an application of a colored decorative film (hereinafter referred to as “paint substitute film”) to an exterior component or the like as substitutes for the painting process has been receiving attention in recent years.
A paint substitute film as conventionally used, for example as disclosed in JP 63-123469 A, has a trilaminar structure including a transparent layer, a pigmented coating, and an adhesive layer. JP 63-123469 A teaches a process of applying the film to a target object to which a decorative effect will be given. The process is schematically illustrated in FIGS. 6A–6D. First, as shown in FIG. 6A, the film 31 is formed three-dimensionally in a supporting mold 32 so as to conform to a contoured surface of the target object; then, as shown in FIG. 6B, end portions of the film 31 are trimmed off. The trimmed film 31 is placed for example into an injection mold 34 as shown in FIG. 6C, and bonded to the target object 33 while the target object 33 is being formed. A resultant casting of a decorated component is taken out of the injection mold 34 as shown in FIG. 6D. Another technique for applying a paint substitute film using an injection mold is disclosed in JP 7-9484 A.
The process of applying a paint substitute film as illustrated in FIGS. 6A–6D require a trimming step using a cutting blade, a laser, a hot wire or the like. In particular, when the target object 33 to which a decorative effect will be given has a complicate shape, a trimmed portion thereof becomes complicate too, and thus the cost incurred for the trimming step would add up, which could eventually raise the total cost of production, thereby making the final casting expensive.
In addition, with the above-described technique using the injection molding, molding of the target object and applying of the paint substitute film are performed simultaneously in the same process step; therefore, the applicable target object (component) should disadvantageously be restricted to those made of materials which can be formed by injection molding.
The present invention has been created to address the above-discussed disadvantages.